Most Vietnamese vocabulary is compounds of syllables you already know. Once you see the joins, new words stop being new. Hold any compound in the app (or highlight it on a laptop) to see its parts — this sheet is the pattern behind what you'll see.
PHẦN I · 01
Three formation types
There are exactly three ways Vietnamese builds a longer word out of shorter ones, and once you can tell them apart, an unfamiliar compound stops being a guess.
1. Coordinate compounds (từ ghép đẳng lập) — A + B = the category
Two related words stand for the whole class. Neither is "the main one."
| word | parts | logic |
|---|---|---|
| quần áo | quần (trousers) + áo (shirt) | two garments → clothes in general |
| bàn ghế | bàn (table) + ghế (chair) | → furniture |
| ăn uống | ăn (eat) + uống (drink) | → eating & drinking, diet |
| đi lại | đi (go) + lại (come back) | → travel, getting around |
| cha mẹ / bố mẹ | father + mother | → parents |
| anh em | older brother + younger sibling | → siblings; "us guys" |
| mua bán | buy + sell | → trading, commerce |
| nhà cửa | house + door | → housing, the home |
| con cái | child + offspring | → children (collectively) |
| sách vở | book + notebook | → books & school things |
The pair often means the category, not "A and B". quần áo isn't "trousers and a shirt" — it's clothes. Ask for một cái áo if you want one shirt.
2. Head + modifier (từ ghép chính phụ) — A is the thing, B narrows it
The first word is the head (unlike English, where the modifier comes first).
| word | parts | logic |
|---|---|---|
| xe đạp | xe (vehicle) + đạp (pedal) | vehicle-you-pedal → bicycle |
| xe máy | xe + máy (machine) | → motorbike |
| xe ôm | xe + ôm (to hug) | vehicle-you-hug → motorbike taxi |
| máy bay | máy (machine) + bay (fly) | → airplane |
| nhà hàng | nhà (house) + hàng (goods) | → restaurant |
| nhà báo | nhà (house/-ist) + báo (news) | → journalist |
| người yêu | người (person) + yêu (love) | → lover, boy/girlfriend |
| nước mắm | nước (liquid) + mắm (fermented fish) | → fish sauce |
| cà phê sữa | coffee + milk | → milk coffee |
| bánh mì | bánh (cake/bread-thing) + mì (wheat) | → baguette |
Productive heads worth memorizing — learn one, unlock dozens: xe (vehicles) · nhà (house/professional) · máy (machines) · nước (liquids) · bánh (breads/cakes) · người (people) · thợ (skilled worker: thợ điện, thợ cắt tóc) · cửa hàng (shops)
3. Reduplicatives (từ láy) — sound-echo words
Half or all of the syllable repeats. Often no standalone meaning — the feel is the meaning. Very common in description and emotion.
| word | pattern | meaning |
|---|---|---|
| lung linh | full echo-ish | shimmering, sparkling |
| lấp lánh | l- l- | glittering |
| xinh xinh | full repeat | cutely pretty (softened) |
| đẹp đẽ | đ- đ- | beautiful (softened/general) |
| vui vẻ | v- v- | cheerful |
| nhanh nhẹn | nh- nh- | nimble, quick |
| lo lắng | l- l- | worried |
| mệt mỏi | m- m- | worn out |
Rule of thumb: repeating softens or generalizes. đẹp = beautiful (sharp, specific); đẹp đẽ = beautiful (general, gentler). Learners over-use the base form; natives reach for the reduplicative in casual description.
PHẦN II · 02
Sino-Vietnamese (Hán-Việt) — the "Latin" layer
About 60% of vocabulary comes from Chinese roots. Formal/academic words are built from bound morphemes that don't stand alone but repeat everywhere.
| root | meaning | shows up in |
|---|---|---|
| học | study (學) | học sinh (student), đại học (university), hóa học (chemistry) |
| viện | institute (院) | bệnh viện (hospital), viện bảo tàng (museum), học viện (academy) |
| bảo | treasure/protect (寶/保) | bảo tàng (museum), bảo vệ (protect/guard), bảo hiểm (insurance) |
| quốc | country (國) | quốc gia (nation), quốc tế (international), Trung Quốc (China) |
| gia | family/-ist (家) | gia đình (family), chuyên gia (expert), quốc gia (nation) |
| sinh | born/life (生) | sinh nhật (birthday), học sinh (pupil), sinh viên (uni student) |
| trường | school/field (場/長) | trường học (school), thị trường (market), trưởng (chief) |
Pattern: Hán-Việt words are usually head-LAST (opposite of native compounds): đại học = big + study = university. bệnh viện = illness + institute = hospital.
PHẦN III · 03
How to use this
Tách từ trước — split before you memorize
When you meet a new long word, split it before committing it to memory — hold it in the app, or highlight it on a computer, to see the parts light up.
Học từ đầu hay dùng — learn the productive heads early
xe, nhà, máy, nước, người — learn one of these heads and you unlock a whole family of words at once.
Học gốc, không học từng từ — for Hán-Việt, learn roots not words
học alone explains twenty different words the moment you know the root, instead of needing twenty separate flashcards.
Đừng ép — some words just are what they are
Reduplicatives like lung linh are opaque on purpose — feel beats parse, and that's fine.
PHẦN IV · 04
If you remember nothing else
Split before you memorize
Most long words are two or three pieces you already know — find the seam before you try to remember the whole thing.
Coordinate compounds name the category, not "A and B"
quần áo means clothes in general, not one pair of trousers plus one shirt.
A few heads unlock dozens of words
xe, nhà, máy, nước, người each open a whole family — learn the head, guess the rest.
Hán-Việt roots repeat everywhere
Learn học, viện, quốc once each and twenty formal words stop being new.